The majority of my day-to-day work is on maxed out iMac, usually connect to four or five external storage devices for backup, Time Machine, mass storage and so on. Clicking through each device in the Finder to check on free storage, or to eject a device is cumbersome and slow. FreeSpace is not. This 99-cent utility monitors each connected storage device and displays free space on the startup volume, but with a click, displays all the details you need for every other connected device.
Click on FreeSpace in the Menubar to display each connected device, the amount of storage, and preferences.
There’s more beyond just listing the amount of space available or remaining on each storage device. Free Space can eject all the connected devices with a click. Or, eject one at a time, even for disks with multiple partitions, which can also be sorted.
FreeSpace also highlights the Menubar icon if free space on any connected device drops below a specific percentage. Even Time Machine can be pinned to the Menubar and notification can be in the Menubar icon or in Notification Center. This is a well done, useful utility with a modest price tag. It’s a shame Apple doesn’t include this capability in OS X.